CN113874233B

CN113874233B - Suspension device

Info

Publication number: CN113874233B
Application number: CN202080037316.1A
Authority: CN
Inventors: 花井诚; 近藤卓宏
Original assignee: KYB Corp
Current assignee: KYB Corp
Priority date: 2019-05-30
Filing date: 2020-05-20
Publication date: 2023-05-30
Anticipated expiration: 2040-05-20
Also published as: JP7132174B2; US20220242185A1; WO2020241403A1; DE112020002628T5; JP2020192935A; CN113874233A; US11801722B2

Abstract

A suspension device (1) is provided with a leaf spring (S) and a damper (2). The leaf spring (S) imparts an elastic force that moves the unsprung member relative to the body (B) (sprung member) of the vehicle (V) in a prescribed direction. The damper (2) has a first expansion/contraction member (10), a second expansion/contraction member (20), an intermediate member (30), and a damping passage (40). The first and second expansion and contraction members (10, 20) form first and second gas chambers (R1, R2) filled with gas therein and are expandable and contractible. The upper ends (10A) and the lower ends (20B) of the first and second expansion and contraction members (10, 20) are connected to the main body (B). An intermediate member (30) connects the first and second expansion and contraction members (10, 20) and to the leaf spring (S). A damping passage (40) connects the first and second gas chambers (R1, R2) to each other, and imparts resistance to the flow of the gas flowing therethrough. One of the first and second expansion and contraction members (10, 20) is contracted when the other is expanded.

Description

Suspension device

Technical Field

The present invention relates to a suspension (suspension) device.

Background

Patent document 1 discloses a conventional suspension device. The suspension device is provided with a damper having an air pressure damper main body, an output shaft, a sealing body, and a damping passage. The air pressure buffer main body is formed in a tubular shape having pressure chambers filled with a gas at both ends. Each pressure chamber is sealed by a sealing body having elasticity and being provided so as to be expandable and contractible. The pressure chambers are communicated with each other through the damper passage, and resistance is given to the flow of the gas flowing through the damper passage. The size of each pressure chamber changes with the expansion and contraction of the sealing body, and the gas can be communicated between the pressure chambers to generate damping force.

Prior art literature

Patent literature

Patent document 1 Japanese patent application laid-open No. 2012-172817

Disclosure of Invention

Technical problem to be solved by the invention

However, the suspension device generally needs to include a suspension spring that applies an elastic force between a spring-up member such as a body (body) and a spring-down member such as a wheel. In the case where the suspension spring is provided in patent document 1, it is necessary to be provided separately from the shock absorber and mounted on the vehicle. In this case, the damper and the mounting portion of the suspension spring need to be separately provided, resulting in a complicated structure.

The present invention has been made in view of the above-described conventional circumstances, and an object of the present invention is to provide a suspension device that can be simplified in structure.

Solution for solving the technical problems

The suspension device of the present invention includes a leaf spring (leaf spring) and a damper. The leaf spring imparts an elastic force that moves the unsprung member relative to the sprung member of the vehicle in a prescribed direction. The damper has a first expanding and contracting member, a second expanding and contracting member, an intermediate member, and a damping passage. The first expanding and contracting member forms a first gas chamber filled with gas therein and is provided to be expandable and contractible. In addition, the first expansion and contraction member has one end connected to a sprung member of the vehicle in the mounted state. The second expansion and contraction member forms a second gas chamber filled with gas therein and is provided so as to be expandable and contractible. In addition, the second expansion and contraction member has one end connected to a sprung member of the vehicle in the mounted state. The intermediate member is disposed between the first expansion member and the second expansion member, and connects the first expansion member and the second expansion member. In addition, the intermediate member is connected to the leaf spring in the mounted state. The damping passage communicates the first gas chamber and the second gas chamber, and imparts resistance to the flow of gas flowing between the first gas chamber and the second gas chamber. One of the first expansion and contraction member and the second expansion and contraction member is contracted when the other is expanded.

Drawings

Fig. 1 is a diagram schematically showing a vehicle having a suspension device according to embodiment 1.

Fig. 2 is an enlarged view of a main portion of fig. 1.

Fig. 3 is a diagram for explaining the operation of the suspension device according to embodiment 1, and shows a state in which the wheel moves upward from the state in fig. 2.

Fig. 4 is a diagram for explaining the operation of the suspension device according to embodiment 1, and shows a state in which the wheel moves downward from the state in fig. 2.

Detailed Description

A specific embodiment of a suspension device according to the present invention will be described with reference to the accompanying drawings. In the following description, the vertical and horizontal directions represent the vertical and horizontal directions of the vehicle, and the vertical and horizontal directions shown in fig. 1 to 4 are respectively represented.

Embodiment 1

As shown in fig. 1 and 2, the suspension device 1 of embodiment 1 is provided in a vehicle V. The suspension device 1 supports a wheel W or the like as an unsprung member so as to be movable in the up-down direction relative to a main body B as an unsprung member of the vehicle V. The suspension device 1 includes a leaf spring S as a suspension spring and a damper 2. The suspension device 1 further includes two suspension arms (suspension arms) 3 and 4. The suspension device 1 is a so-called double arm (double wishbone) in which the two

suspension arms

3, 4 are arranged vertically in parallel. The

suspension arms

3 and 4 are rotatably supported by the main body B. Specifically, the base end side of the suspension arm 3 is rotatably supported about a rotation axis Cl extending in the front-rear direction of the vehicle V. The base end side of the suspension arm 4 is rotatably supported about a rotation axis C2 set below the rotation axis Cl. The rotation shaft C2 is set to extend in the front-rear direction of the vehicle V, similarly to the rotation shaft Cl. The front end sides of the

suspension arms

3 and 4 extend from the base end side to the left-right direction (left direction in fig. 1) of the vehicle V, and are rotatably connected to a joint (knuckle) K on the wheel W side.

The leaf spring S gives an elastic force in a direction in which the wheel W moves downward relative to the body B. The leaf spring S of the present embodiment is made of glass fiber reinforced plastic (GFRP, glass fiber reinforced plastics). The leaf springs S are arranged so as to extend in the left-right direction of the vehicle V. The leaf springs S are provided one for each of the left and right wheels W in a pair. The center portion S1 of the leaf spring S is connected to the main body B, and the left and right end portions S2 are supported by the suspension arm 4. Specifically, as shown in fig. 1 and 2, a central portion S1 of the leaf spring S is fixed to the main body B by a bracket (black) B1, and an end portion S2 of the leaf spring S is fixed to a fixing portion 4A of the suspension arm 4 by means of a rubber bushing (rubber bush) G.

In the vehicle V according to embodiment 1, the main body B supported by the leaf spring S and various members and the like fixedly disposed with respect to the main body B are sprung members, and the various members and the like suspended from the leaf spring S and disposed so as to be movable with respect to the main body B, such as the wheel W, the joint K, the

suspension arms

3, 4, and the like, are unsprung members. The damper 2 suppresses the relative movement of the sprung member group and the unsprung member group in the state of the elastic force of the suspension springs by imparting resistance to the relative movement thereof to attenuate them. The damper 2 is mounted between a main body B as a sprung member and a leaf spring S that is partially relatively moved with respect to the main body B by flexural deformation.

As shown in fig. 1 and 2, the damper 2 includes a first expansion and contraction member 10, a second expansion and contraction member 20, an intermediate member 30, and a damping passage 40. The first expansion and contraction member 10 forms a first gas chamber R1 filled with gas therein and is provided so as to be expandable and contractible. Specifically, the first expansion and contraction member 10 is a rubber roller (rolling lobe) formed in a cylindrical shape, and is provided so as to be expandable and contractible in the axial direction. The first expansion and contraction member 10 is connected to the main body B at an upper end 10A, which is one end in the expansion and contraction direction, in a state of being mounted on the vehicle V. The lower end 10B, which is the other end of the first expansion and contraction member 10 in the expansion and contraction direction, is connected to the intermediate member 30. The second expansion and contraction member 20 forms a second gas chamber R2 filled with gas therein, and is provided so as to be expandable and contractible. In the present embodiment, the second expansion and contraction member 20 is a cylindrical rubber roller (rolling lobe) having substantially the same structure and size as the first expansion and contraction member 10. The second expansion and contraction member 20 is connected to the main body B at a lower end 20B, which is one end in the expansion and contraction direction, in a state of being mounted on the vehicle V. An upper end 20A, which is the other end of the second expansion and contraction member 20 in the expansion and contraction direction, is connected to the intermediate member 30.

The intermediate member 30 is arranged between the first and second expanding and

contracting members

10, 20. As described above, the intermediate member 30 is connected with the lower end 10B of the first expanding and contracting member 10 and the upper end 20A of the second expanding and contracting member 20. Thus, the intermediate member 30 of the present embodiment connects the first expansion and contraction member 10 and the second expansion and contraction member 20 in series in the expansion and contraction direction. In the attached state, the intermediate member 30 is connected to a position closer to the wheel than the fixed position on the main body B side of the leaf spring S. In the case of the present embodiment, as shown in fig. 1 and 2, the center portion S1 of the leaf spring S is fixed to the main body B by a bracket (brecket) B1, and the end portions S2 are fixed to the fixing portions 4A of the suspension arms 4. The intermediate member 30 is connected to a portion separated from the center portion S1 of the leaf spring S, and this portion is a portion movable relative to the main body B. Specifically, the intermediate member 30 is connected to a portion separated from the center portion S1 toward the end portion S2 of the leaf spring S by a bracket B2.

The damping passage 40 communicates the first gas chamber R1 and the second gas chamber R2, and imparts resistance to the flow of gas flowing between the first gas chamber R1 and the second gas chamber R2. In the case of the present embodiment, as shown in fig. 2, the damper passage 40 is configured to have a first damper passage 41 and a second damper passage 42. The first damping passage 41 is configured to include: a check valve 41A that allows the flow of gas from the first gas chamber R1 to the second gas chamber R2 and prevents the opposite flow thereof; and a flow control valve 41B for controlling the flow rate of the circulating gas. The second damper passage 42 is configured to include: a check valve 42A that allows the flow of gas from the second gas chamber R2 to the first gas chamber R1 and prevents the opposite flow thereof; and a flow control valve 42B for controlling the flow rate of the circulating gas. In the present embodiment, the first damper passage 41 and the second damper passage 42 are formed in such a manner that the flow resistance of the gas varies according to the flow control of the

flow control valves

41B and 42B. Specifically, the flow resistance of the second damper passage 42 is set to be larger than the flow resistance of the first damper passage 41. In the present embodiment, the

check valves

41A and 42A and the

flow control valves

41B and 42B are integrally provided with the intermediate member 30.

The damper 2 of the present embodiment is provided so as to be movable in the extending direction of the leaf spring S. In detail, as shown in fig. 2, the damper 2 is capable of changing the fixing position of the intermediate member 30 by the bracket B2 along the leaf spring S extending in the left-right direction.

Next, the operation of the suspension device 1 according to embodiment 1 will be described.

In the vehicle V, the damper 2 is in a state in which the pressures of the first gas chamber R1 and the second gas chamber R2 are balanced in a state in which the wheels W do not undergo relative movement with respect to the main body B. In this state, no gas flows between the first gas chamber R1 and the second gas chamber R2, and no damping force is generated.

In the vehicle V, when the wheel W moves upward relative to the body B due to an input from a road surface or the like, for example, when the state shown in fig. 2 is changed to the state shown in fig. 3, the front end sides of the

suspension arms

3 and 4 move upward accordingly. Since the central portion S1 of the leaf spring S is connected to the main body B via the bracket B1 and the end portion S2 is connected to the fixed portion 4A of the suspension arm 4, the end portion S2 is deformed by bending in such a manner as to move upward relative to the central portion S1.

In the leaf spring S, a portion between a portion connected to the central portion S1 of the body B via the bracket B1 and a portion fixed to the suspension arm 4 via the fixing portion 4A is connected to the intermediate member 30 of the damper 2 via the bracket B2. Therefore, the intermediate member 30 moves upward as the end portion S2 of the leaf spring S moves upward. Accordingly, the first expanding and contracting member 10 contracts in the up-down direction and the volume of the first gas chamber R1 decreases. On the other hand, the second expansion and contraction member 20 expands in the up-down direction, and the volume of the second gas chamber R2 increases. Thereby, the gas in the first gas chamber R1 is compressed to increase in pressure, and the gas in the second gas chamber R2 is expanded to decrease in pressure. That is, a pressure difference is generated between the first gas chamber R1 and the second gas chamber R2. According to this pressure difference, a flow of gas flowing through the damper passage 40 is generated.

Specifically, the first damping passage 41 allows the flow from the first gas chamber R1 to the second gas chamber R2. On the other hand, the second damping passage 42 does not generate the circulation of gas due to the clogging of the check valve 42A. Thereby, a damping force is generated by the flow control valve 41B of the first damping passage 41, and the upward relative movement of the wheel W with respect to the main body B is suppressed.

On the other hand, in the case where the wheel W moves downward relative to the body B in the vehicle V, for example, when the state shown in fig. 2 is changed from the state shown in fig. 4, the leaf spring S flexes and deforms so that the end portion S2 moves downward relative to the center portion S1. Thus, the intermediate member 30 moves downward. In response, the first expansion and contraction member 10 expands in the up-down direction to increase the volume of the first gas chamber R1, and the second expansion and contraction member 20 contracts in the up-down direction to decrease the volume of the second gas chamber R2. Thereby, the gas in the first gas chamber R1 expands to decrease in pressure, and the gas in the second gas chamber R2 is compressed to increase in pressure. That is, a pressure difference is generated between the first gas chamber R1 and the second gas chamber R2. According to this pressure difference, a flow of gas flowing through the damper passage 40 is generated.

Specifically, the second damper passage 42 allows the flow from the second gas chamber R2 to the first gas chamber R1. On the other hand, the first damping passage 41 does not generate the circulation of gas due to the clogging of the check valve 41A. Thereby, a damping force is generated by the flow control valve 42B of the second damping passage 42, and downward relative movement of the wheel W with respect to the main body B is suppressed.

In the suspension device 1, the damper 2 is moved in the extending direction of the leaf spring S, whereby the magnitude of the damping force generated by the damper 2 can be changed. Specifically, as shown in fig. 2, the upper end 10A of the first expansion and contraction member 10 and the lower end 20B of the second expansion and contraction member 20 of the damper 2 are in contact with the contact surface portions Al, A2 of the body B. The first expansion and contraction member 10 and the second expansion and contraction member 20 change the volumes of the gas chambers R1, R2 by expanding and contracting between the abutment surfaces Al, A2 of these main bodies B and the intermediate member 30. The intermediate member 30 is displaced between the abutment surfaces Al, A2 of the body B according to the magnitude of the deflection displacement of the leaf spring S. The leaf spring S is increased in deflection displacement at a position far from the bracket B1 as a fixed position on the main body B side, that is, a position closer to the end portion S2 than a position closer to the wheel W.

Therefore, by moving the damper 2 in the extending direction of the leaf spring S to change the fixing position of the bracket B2, the magnitude of the displacement of the intermediate member 30 when the leaf spring S is subjected to the flexural displacement by the relative movement between the body B of the vehicle V and the wheel W changes, and the magnitudes of the amounts of change in the volumes of the 1 st expansion and contraction member 10 and the 2 nd expansion and contraction member 20 change. Thereby, the flow rate of the gas flowing through the damper passage 40 changes. Therefore, in the suspension device 1, the damper 2 is moved in the extending direction of the leaf spring S to adjust the displacement of the intermediate member 30, thereby adjusting the expansion and contraction amounts of the first expansion and contraction member 10 and the second expansion and contraction member 20, and thereby generating a damping force of a desired magnitude.

As described above, in the suspension device 1 according to embodiment 1, one end of the two expansion and

contraction members

10 and 20 of the damper 2, that is, the upper end 10A of the first expansion and contraction member 10 and the lower end 20B of the second expansion and contraction member 20 are connected to the main body B, and the intermediate member 30 connecting the two expansion and

contraction members

10 and 20 is connected to the leaf spring S. Therefore, when a flexural displacement is generated on the leaf spring S due to the relative movement between the body B of the vehicle V and the wheel W, one of the two expansion and

contraction members

10, 20 of the shock absorber 2 expands, while the other contracts. Thereby, the gas filled in the two gas chambers R1, R2 is expanded one while the other is compressed to generate a pressure difference, thereby generating a flow of the gas flowing through the damping passage 40. The gas is given resistance when the damper passage 40 is circulated. The shock absorber 2 can apply the resistance as a damping force that suppresses the relative movement between the body B of the vehicle V and the wheel W. In addition, the suspension device 1 integrally connects the leaf spring S as a suspension spring and the intermediate member 30 of the damper 2. Therefore, it is possible to mount the suspension spring and the damper to the vehicle with a simple structure, as compared with the case where the suspension spring and the damper are provided separately.

Therefore, the suspension device 1 of embodiment 1 can be simplified in structure.

In the suspension device 1 according to embodiment 1, the damper 2 is provided so as to be movable in the extending direction of the leaf spring S, and therefore the magnitude of the resistance force can be easily adjusted. Thus, the magnitude of the damping force can be easily adjusted.

The present invention is not limited to embodiment 1 described in the above description and the drawings, and for example, the following embodiments are also included in the technical scope of the present invention.

(1) In embodiment 1, the suspension device is illustrated as a double a-arm type, but the form and the like of the suspension device according to the present invention are not limited to this as long as they are provided with leaf springs.

(2) In embodiment 1, the leaf spring is illustrated as extending in the left-right direction of the vehicle, but the leaf spring according to the present invention may extend in a direction other than the left-right direction of the vehicle, such as the front-rear direction. The material of the leaf spring is not limited to GFRP, and may be other materials such as metal.

(3) In embodiment 1, the plate spring is fixed to the lower suspension arm, but the present invention is not limited to this. If there are a plurality of suspension arms, the leaf spring may be fixed to any one of the suspension arms. The leaf spring may be fixed to an unsprung member other than the suspension arm. The leaf spring may be directly attached to a spring-down member such as a suspension arm without using a rubber bushing.

(4) In embodiment 1, the plate spring is illustrated as having a central portion connected to the main body and end portions connected to the suspension arm as the suspension arm, but the plate spring according to the present invention may have an end portion connected to the main body and a central portion or the other end portion connected to the suspension arm or other suspension arm.

(5) In embodiment 1, the first expansion and contraction member and the second expansion and contraction member are provided in substantially the same configuration and size, but the configuration and size of the two expansion and contraction members may be different.

(6) In embodiment 1, the first expansion and contraction member and the second expansion and contraction member are each in the form of a roller blade, but the first expansion and contraction member and the second expansion and contraction member may be members in other forms such as a corrugated tube made of metal. The material of the first expansion and contraction member and the second expansion and contraction member is not limited to rubber, and other materials such as metal and resin may be used.

(7) In embodiment 1, the first expansion and contraction member is movably provided along the extending direction of the suspension arm, but the second expansion and contraction member may be movably provided along the extending direction of the suspension arm, or the two expansion and contraction members may be movably provided along the extending direction of the suspension arm.

(8) In embodiment 1, the form in which two damping passages, i.e., the first damping passage and the second damping passage, are provided is illustrated as the damping passage, but this is not essential in the present invention. As a mode of providing the damper passage, for example, a mode may be adopted in which only one damper passage imparting resistance is provided, the passage imparting resistance to the flow of gas flowing from the first gas chamber to the second gas chamber or the flow of gas flowing from the second gas chamber to the first gas chamber, and a passage imparting no resistance to the flow of the other gas is provided.

(9) In embodiment 1, the form in which the damper passage is formed in the intermediate member is exemplified, but in the present invention, the damper passage may be formed separately from the intermediate member.

(10) In embodiment 1, the body of the vehicle is exemplified as the sprung member, but the sprung member according to the present invention is not limited to this.

(11) In embodiment 1, the first expansion and contraction member and the second expansion and contraction member are expanded and contracted in a predetermined direction, that is, are provided so as to be extendable and contractible in a predetermined direction, but this is not essential. At least one of the first expanding and contracting member and the second expanding and contracting member according to the present invention may be expanded and contracted without having a predetermined directivity, such as a balloon.

Description of the reference numerals

1 … suspension 2 … damper

3. 4A … fixing portion of 4 … suspension arm

10 … first expansion and contraction member

The upper end of the first expansion and contraction member of 10A …

10B … lower end of first expansion and contraction member

20 and … second expansion and contraction member

The upper end of the 20A … second expansion and contraction member

Lower end of 20B … second expansion member

30 … intermediate member 40 … damping channel

41 … first damping

channel

41A, 42A … check valve

41B, 42B … flow control valve 42 … second damping passage

Main body of contact surface B … (spring upper material) of Al, A2 …

B1 … support B2 … support

C1 … rotation axis C2 … rotation axis

G … rubber bushing K … section

R1 … first gas chamber R2 … second gas chamber

S … leaf spring

S1 … center portion S2 … end portions

V … vehicle W … wheel

Claims

1. A suspension device is characterized by comprising a leaf spring and a damper, wherein,

the leaf spring imparts an elastic force that moves the unsprung member relative to the sprung member of the vehicle in a prescribed direction,

the buffer has:

a first expansion/contraction member that forms a first gas chamber filled with gas therein and is provided so as to be expandable/contractible, one end of the first expansion/contraction member being connected to the sprung member in an installed state;

a second expansion/contraction member that forms a second gas chamber filled with gas therein and is provided so as to be expandable/contractible, one end of the second expansion/contraction member being connected to the sprung member in an installed state;

an intermediate member that connects the first expansion and contraction member and the second expansion and contraction member, and that is connected to the leaf spring in an installed state;

a damper passage that communicates the first gas chamber and the second gas chamber and that imparts resistance to the flow of the gas flowing between the first gas chamber and the second gas chamber,

one of the first expanding member and the second expanding member is contracted when the other is expanded.